Engineering Bulletin: Blank Design

An incorrectly sized blank diameter can result in thread rolling issues like tapered threads, slivers and flakes, and off-size threads.

Blank design, therefore, is an important consideration in the thread rolling process to ensure parts are manufactured to the highest quality.

Important factors to consider during blank design include:

Blank diameter

Chamfer angle

Shoulder clearance

Thread length vs. roll length

Changes to the blank diameter will affect the major diameter of the thread by a ratio of 3 to 1. So, for every .001” that the blank diameter is adjusted, the thread’s major diameter will change by .003”.

CJWinter compiled helpful diagrams of blank diameter, chamfer angle, and other dimensions involved in blank design so you can quickly identify or correct any thread rolling issues you may be having.

Click through the slides below to learn more about blank design properties.

Lib has been with the Brinkman International Group, Inc. for the last 30 years. Currently the Director of Global Sales, Lib has held numerous positions in Engineering, Operations, Sales and Product Management with CJWinter and its manufacturing divisions. Lib is a member and has served on governing boards for the Society of Automotive Engineers, The American Society of Mechanical Engineers, and Precision Machine Products Association.